bueno, no lo he probado, pues es bastante complicado.
se necesita el chip infecus, hacer un timing atack y dongradear al kernel que tiene el hypervisor vulnerable y no se qué más historias... pero parece ser q lo han logrado.
http://www.xbox-scene.com/xbox1data/sep/EEAVZyAEyAnmBgipsf.php
http://gueux-forum.net/index.php?showtopic=174687
However it's not something that everyone out there can do (yet) as you'll need your CPU key (via Hypervisor Exploit and if you got banned it means you're on the latest kernel so you'll need to perform the 'Timing Attack' to downgrade first). You'll also need all the tools to read/flash your Xbox 360 NAND (with the Infectus chip for example).
Here are the things he tried:
* downgrade banned 5787 PAL to 4532 NTSC U, updated again to 5787 via HD. Still banned.
* downgrade banned 5787 PAL to 1888 PAL, updated again to 5787 via HD. Still banned.
* Patched 1888 PAL dump with the last number of the Xbox 360 serial in the keyvault (location A0 to AB) changed. Still banned.
* Patched 1888 PAL dump with the all the numbers of the Xbox 360 serial in the keyvault changed. Still banned.
* Replaced keyvault in the 1888 PAL dump of the banned console with keyvault of an unbanned console. Connected to LIVE OK, updated to latest kernel online OK, still connects fine to LIVE.
It's a bit like the Xbox1 EEPROM 'hack' ... except that (at least for now) it's much harder to perform yourself on Xbox360.
en el foro de scene se habla ya de ello:
http://www.elotrolado.net/hilo_Franchute-afirma-haber-logrado-desbanear-una-360_892796 